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Smallaxe
09-27-2011, 05:29 PM
There seems to be a real problem determining what thatch is... Conversations about thatch have become impossible because one person is thinking grass clippings and another is thinking, living and dead roots and stems growing in a tangled mess above the surface of the soil...

This dense layer is typically hydrophobic and keeps the ferts and water at or near the surface, thus perpetuating the problem with roots continuing to grow upwards where the N is...
It is this kind of thatch that is man-made and it it this kind of thatch that aeration is designed to overcome the problems of...

Question is : What do we call grass clippings and are they even a problem?

ArenaLandscaping
09-27-2011, 05:42 PM
Thatch is a build-up of organic matter which can include, dead grass leaves, stems, stolons, rhizomes and overcrowded grass roots and lateral weed growth. Thatch can stifle the growth and health of grass or turf. Removing the thatch helps the grass by encouraging it to thicken up and also makes it stronger and less susceptible to disease. Reducing thatch levels increases the levels of water, air and nutrients that can get through to the root zone of the grass plants. Significant thatch problems in lawns can cause diseases and can encourage moss to grow in the areas where grass has died. A by-product of scarifying or de-thatching is that moss is also removed, and depending on how deep the scarifying blades are set, root cutting can also occur, and this in turn helps grass to thicken up over time. Scarifying is normally carried out in autumn or spring. When scarifying or de-thatching not all thatch should be removed as a small amount of thatch is beneficial to the lawn. A lawn that has excessive thatch may feel spongy when trod upon. After removing thatch, it can be swept or raked up using a lawn sweeper.
http://en.wikipedia.org/wiki/Dethatcher

Smallaxe
09-27-2011, 06:22 PM
Thatch is a build-up of organic matter which can include, dead grass leaves, stems, stolons, rhizomes and overcrowded grass roots and lateral weed growth. Thatch can stifle the growth and health of grass or turf. Removing the thatch helps the grass by encouraging it to thicken up and also makes it stronger and less susceptible to disease. Reducing thatch levels increases the levels of water, air and nutrients that can get through to the root zone of the grass plants. Significant thatch problems in lawns can cause diseases and can encourage moss to grow in the areas where grass has died. A by-product of scarifying or de-thatching is that moss is also removed, and depending on how deep the scarifying blades are set, root cutting can also occur, and this in turn helps grass to thicken up over time. Scarifying is normally carried out in autumn or spring. When scarifying or de-thatching not all thatch should be removed as a small amount of thatch is beneficial to the lawn. A lawn that has excessive thatch may feel spongy when trod upon. After removing thatch, it can be swept or raked up using a lawn sweeper.
http://en.wikipedia.org/wiki/Dethatcher

Vertical mower/dethatcher destructive:

http://urbanext.illinois.edu/lawnchallenge/lesson5.html
"Thatch may be torn out with a dethatcher or vertical mower, but will most likely return unless the cause is corrected. Mechanical dethatching is also very destructive to the lawn because roots are in thatch instead of soil, so plants tear out easily. Overseeding is usually required afterwards. For this reason, it's best to tear out thatch in late August for optimum reseeding timing. "

no real attention paid to grass leaves as wikipedia states
"Thatch is a layer of living and dead organic matter that occurs between the green matter and the soil surface....The primary component of thatch is turfgrass stems and roots. It accumulates as these plant parts buildup faster than they breakdown."

Regardless, is it acceptable to call a layer of grass clippings "Thatch" and should it be regarded and treated the same was as the living and dead roots and stems??

JDiepstra
09-27-2011, 06:31 PM
Wow youre really making a big deal about this! All that stuff between the grass blade and the soil..... Thats thatch.

ArenaLandscaping
09-27-2011, 06:35 PM
Regardless, is it acceptable to call a layer of grass clippings "Thatch" and should it be regarded and treated the same was as the living and dead roots and stems?? [/b]

I believe it is acceptable to say that grass clipping can be regarded as thatch. Over time they add to the thatch layer/buildup.

olcllc
09-27-2011, 07:36 PM
Wow youre really making a big deal about this! All that stuff between the grass blade and the soil..... Thats thatch.

Well said!!!:clapping:

MJS
09-28-2011, 07:25 PM
I believe it is acceptable to say that grass clipping can be regarded as thatch. Over time they add to the thatch layer/buildup.

You would be surprised, that has rarely been my experience. Unless the clippings are excessively long or thick, they disintegrate and are absorbed, at least partially, as nitrogen by the grass that is growing. Clippings are almost never a cause of excess thatch.

ArenaLandscaping
09-28-2011, 07:49 PM
You would be surprised, that has rarely been my experience. Unless the clippings are excessively long or thick, they disintegrate and are absorbed, at least partially, as nitrogen by the grass that is growing. Clippings are almost never a cause of excess thatch.

Grass clippings are not the cause of thatch, they add to the thatch layer "over time". An accumulation of wet grass clipping that do not have enough time to decompose over time or in between cuts will be left in the thatch layer. It all depends on the mowing practices.

Smallaxe
09-28-2011, 08:18 PM
Unfortunately, none of these comments relate to the "University Extension" articles that have been posted recently, including the one in this thread...

Don't Overthink this... we're just looking for a definition of 'thatch' that gives us a point of impact on a cause and solution... No big deal... :)

Darryl G
09-28-2011, 08:20 PM
I call grass clipping grass clippings. What else would you call them?

I rarely see any significant thatch layer where I am. I will do a tine rake dethatching on some lawns in the spring, but it's mostly to comb out some of the dead grass and matted leaves and twigs. If i can easily get my finger down to bare soil, I consider the thatch layer insignificant and don't worry about it. I think that if you have to dig and wiggle your finger to get it through to soil, that's when it could be a problem. I have never used a power dethatcher though and have never felt the need for one.

Smallaxe
09-28-2011, 08:50 PM
I call grass clipping grass clippings. What else would you call them?

I rarely see any significant thatch layer where I am. I will do a tine rake dethatching on some lawns in the spring, but it's mostly to comb out some of the dead grass and matted leaves and twigs. If i can easily get my finger down to bare soil, I consider the thatch layer insignificant and don't worry about it. I think that if you have to dig and wiggle your finger to get it through to soil, that's when it could be a problem. I have never used a power dethatcher though and have never felt the need for one.

How your finger 'feels' or how much digging through 'grass clippings' with your finger is necessary to make you feel OK, has nothing to do with the cause, prevention, or solution to thatch...

In truth, grass clippings have nothing to do with thatch, and I find it discouraging that nobody can see that...

Your finger would not feel "Real thatch" , but I should not expect you to understand that...

OH , WAIT,,, this isn't the Homeowners Forum... :laugh:

Darryl G
09-28-2011, 08:57 PM
You gonna make me prove you wrong again? lol

fl-landscapes
09-28-2011, 09:05 PM
Not sure why you say no one can see what thatch is. Grass clippings don't really contribute to thatch. Mostly because grass blades decompose quickly where as crowns stolons rhizomes are much harder to decompose and that's why they out compete the natural decomposition process when over watered and or over fertilized.


How your finger 'feels' or how much digging through 'grass clippings' with your finger is necessary to make you feel OK, has nothing to do with the cause, prevention, or solution to thatch...

In truth, grass clippings have nothing to do with thatch, and I find it discouraging that nobody can see that...

Your finger would not feel "Real thatch" , but I should not expect you to understand that...

OH , WAIT,,, this isn't the Homeowners Forum... :laugh:
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Smallaxe
09-28-2011, 09:18 PM
Not sure why you say no one can see what thatch is. Grass clippings don't really contribute to thatch. Mostly because grass blades decompose quickly where as crowns stolons rhizomes are much harder to decompose and that's why they out compete the natural decomposition process when over watered and or over fertilized.



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Hey , fl-landscapes... when you agree with me , that only confuses the issue!!!

What's your point??? :)

Darryl G
09-28-2011, 09:25 PM
How your finger 'feels' or how much digging through 'grass clippings' with your finger is necessary to make you feel OK, has nothing to do with the cause, prevention, or solution to thatch...

In truth, grass clippings have nothing to do with thatch, and I find it discouraging that nobody can see that...

Your finger would not feel "Real thatch" , but I should not expect you to understand that...

OH , WAIT,,, this isn't the Homeowners Forum... :laugh:

I was answering your question. You asked what we call grass clippings. I call them grass clippings.

My point...which it appears you missed...was that on the lawns I service, I can poke my finger right into the soil. If there was a thatch problem, would my finger not encounter some sort of resistance to penetration of the soil? It's a layer right...so if there is an absense of a layer, that means there's no significant thatch, right? I suggest you take your finger and stick it in and wiggle it a little and tell me if it works.

fl-landscapes
09-28-2011, 09:28 PM
Hey , fl-landscapes... when you agree with me , that only confuses the issue!!!

What's your point??? :)

When your right your right, saw a debate and wanted to give my opinion that's all.
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Smallaxe
09-28-2011, 10:15 PM
I was answering your question. You asked what we call grass clippings. I call them grass clippings.

My point...which it appears you missed...was that on the lawns I service, I can poke my finger right into the soil. If there was a thatch problem, would my finger not encounter some sort of resistance to penetration of the soil? It's a layer right...so if there is an absense of a layer, that means there's no significant thatch, right? I suggest you take your finger and stick it in and wiggle it a little and tell me if it works.

Well then... Wouldn't you also say that if your finger couldn't reach the soil because there was an obstruction made up od living and dead roots and stems.... that there may be a situation... :laugh:

define thatch, not grass clippings... :)

Darryl G
09-28-2011, 10:28 PM
Like I said...take your finger and stick it in and wiggle it :p

JFGauvreau
09-29-2011, 07:43 AM
Definition of thatch would be : Take a knife and cut a piece of lawn, see that thatch for yourself. For me, for where I live, on the top layer of that thatch, their will be dead grass clippings, on the bottom of that thatch layer, their is no dead grass clippings. This tells me that the dead grass decompose faster then the rest, thus not building up over the year, so that's why I don't consider dead grass clippings as thatch in my book.

Smallaxe
09-30-2011, 07:24 AM
Definition of thatch would be : Take a knife and cut a piece of lawn, see that thatch for yourself. For me, for where I live, on the top layer of that thatch, their will be dead grass clippings, on the bottom of that thatch layer, their is no dead grass clippings. This tells me that the dead grass decompose faster then the rest, thus not building up over the year, so that's why I don't consider dead grass clippings as thatch in my book.

Very descriptive and well put... If the extension office writers were as articulate, then perhaps people reading what they're saying wouldn't come away with such wild ideas...

RigglePLC
09-30-2011, 10:48 AM
We seldom dethatch around here, anymore. Only when customers request power-raking in spring. And the real reason they want it power raked is that they think it will green up sooner--if the dead grass blades of winter are raked out. The brown appearance in spring around here is mostly due to the fact that some types of Kentucky bluegrass (particularly the elite types) green up very slowly in spring. In my view thatch is a manifestation of an aggressive cultivar with strong rhizomes. I don't feel it causes disease.

Smallaxe
10-01-2011, 08:30 AM
We seldom dethatch around here, anymore. Only when customers request power-raking in spring. And the real reason they want it power raked is that they think it will green up sooner--if the dead grass blades of winter are raked out. The brown appearance in spring around here is mostly due to the fact that some types of Kentucky bluegrass (particularly the elite types) green up very slowly in spring. In my view thatch is a manifestation of an aggressive cultivar with strong rhizomes. I don't feel it causes disease.

Your lawns may be cared for properly, therefore it is unnecessary to deal with thatch at all... :)

Thatch is indeed the results actively growing rhizomes, but the problem is they are all growing up, instead of down or laterally, to get the frequent water and constant supply of N at the surface of the turf...

Once this become hydrophobic it become a viscious cycle of unhealthy growth, which makes the turf susceptible to disease, whether or not it is a 'cause', or not,... it is a definate weakening of the plant...

Would you agree, that the extension offices are saying that?

bonzo1012
10-04-2011, 10:42 PM
I was answering your question. You asked what we call grass clippings. I call them grass clippings.

My point...which it appears you missed...was that on the lawns I service, I can poke my finger right into the soil. If there was a thatch problem, would my finger not encounter some sort of resistance to penetration of the soil? It's a layer right...so if there is an absense of a layer, that means there's no significant thatch, right? I suggest you take your finger and stick it in and wiggle it a little and tell me if it works.

For everyone who didnt take turf management. Thatch layer is the shoot layer between blade and soil. You will be abl to see this layer by taking a plug(not poking around your finger you will never determine dpth this way) A thin thach layer is ok as it protects the crown and gives the lawn its verdure or cushion. Too much creates water runnoff and less fert uptake as it doesnt penetrate as well to the root zone. Root dpth has nothing to do with thatch layer but the soil porosity itself.(sandy,loam, clay). The grass that produces teh most thatch layer is your bentgrass then kentucky then ryegrass and finaly fescues. Fescues are a bunch type grass meening they dont have stolons or rhizomes. I could go on and on but as a lot of peopl have said grass clippings have absolutly nothing to do with the thach layer.

Smallaxe
10-05-2011, 09:31 AM
For everyone who didnt take turf management. Thatch layer is the shoot layer between blade and soil. You will be abl to see this layer by taking a plug(not poking around your finger you will never determine dpth this way) A thin thach layer is ok as it protects the crown and gives the lawn its verdure or cushion. Too much creates water runnoff and less fert uptake as it doesnt penetrate as well to the root zone. Root dpth has nothing to do with thatch layer but the soil porosity itself.(sandy,loam, clay). The grass that produces teh most thatch layer is your bentgrass then kentucky then ryegrass and finaly fescues. Fescues are a bunch type grass meening they dont have stolons or rhizomes. I could go on and on but as a lot of peopl have said grass clippings have absolutly nothing to do with the thach layer.

Don't forget about the roots that grow upward to help form this unnatural layer and the causes of it... :)

TruSomethingOrOther
03-10-2012, 12:46 AM
For everyone who didnt take turf management. Thatch layer is the shoot layer between blade and soil. You will be abl to see this layer by taking a plug(not poking around your finger you will never determine dpth this way) A thin thach layer is ok as it protects the crown and gives the lawn its verdure or cushion. Too much creates water runnoff and less fert uptake as it doesnt penetrate as well to the root zone. Root dpth has nothing to do with thatch layer but the soil porosity itself.(sandy,loam, clay). The grass that produces teh most thatch layer is your bentgrass then kentucky then ryegrass and finaly fescues. Fescues are a bunch type grass meening they dont have stolons or rhizomes. I could go on and on but as a lot of peopl have said grass clippings have absolutly nothing to do with the thach layer.

I agree! Grass clippings only are an issue (as someone else stated) when it's in spring time, damp grass that's overly long, gets discharged back onto the lawn and does not have time to decompose (or is small enough to do such, or the lawn isn't healthy enough) before next mowing and / or rainfall. Taking a core sample from aerating is the best way IMO to determine the thickness of thatch build up. If the lawn is regularly fertilized, discharging the grass clippings from weekly mowing is beneficial in many ways, including growth.

If the lawn needs it, I know my front yard does (dogs are in back - what yard
?), I encourage it.

Exact Rototilling
03-10-2012, 01:16 AM
Subscribing ...too spent to comment at this time....maybe later.
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aeration
03-10-2012, 07:16 PM
When I explain to the customer that thatch appears like peat moss on top of the core and I explain the purpose, benefits, and negative aspects of too much thatch, I'm typically asked "Then what is the dead stuff on top." I usually reply "It's just dead stuff on top."

Aeration, from my experience, doesn't remove the "dead stuff on top." I won't use a dethatcher either. Too rough and stressful on the lawns. Actually, I've had success with a cheap tow-behind "dethatcher" that I refer to as a power rake. The cheap ones sold at TS or Sears, etc. Small tines with a spring on the top that drag/scrape the top of the soil. They are not good for bringing up thatch, as they don't have enough pressure to cut through the soil and dig into it, but they scratch up and loosen the "dead stuff on top."

Smallaxe
03-11-2012, 09:16 AM
I will soon be adding molasses to the lawns once the grass starts growing. The purpose of this is to more quickly digest the suface debris and open up the pathways for water/soluable ferts, to actually soak into the soil...
As the material decays into the soil beneath it begins the process of building a soil structure that continues to expedite perculation and this will also be producing nutrients for the turf...
Of course, the biggest part of dealing with real thatch, will be prevention... I will not fertilize any lawns till after the 3rd mowing at least, or early May if we mow all of April...

Smallaxe
03-11-2012, 09:36 AM
... Actually, I've had success with a cheap...

I got to thinking about this part of your statement, and realized that "success" is quite a loaded term...

How do you define success?

Exact Rototilling
03-11-2012, 01:41 PM
Well whatever thatch is .....? Clients just want the dormant grass scrubbed out to make them feel better. As I have mentioned before my lawn has over 1/2" of thatch. As a spring fertilizer I applied only pelletized dried poultry waste DPW. 100% organic. In fact I'm only promoting fertilizer that has DPW in it this year. I will not put down synthetic high nitrogen fert unless it is a special.request. DPW will be helpful in NOT contributing to further thatch. The back lawn will be a test bed for different application rates of molasses.

My question or angle.is ......Do we need warmer temps to get the most bang for.the Buck for molasses application?


Well I did some 2.0" low mows on my lawn and in other spots 1.5". Other areas spring tine power raked a few other test areas. Other areas of the lawn will not be touched until it needs to be.mowed. I've documented this with pictures and I'm going to mark with white paint the borders of each area with just enough to be able to keep it visible.
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Exact Rototilling
03-11-2012, 01:48 PM
I will offer full throttle flail blade down and deep dirty for true thatch removal but it will be brutally expensive as it generates tremendous haul off.

Going to offer double, triple and quad passes with my Plugr ® 850's for a truly revolving amount of cores that the rolling tine guys can't touch. Followed by a G6 gator blade core break up.
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Exact Rototilling
03-11-2012, 02:12 PM
REVOLTING amount of cores..... blasted Droid auto correct
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Smallaxe
03-11-2012, 10:20 PM
Well whatever thatch is .....? Clients just want the dormant grass scrubbed out to make them feel better. As I have mentioned before my lawn has over 1/2" of thatch. As a spring fertilizer I applied only pelletized dried poultry waste DPW. 100% organic. In fact I'm only promoting fertilizer that has DPW in it this year. I will not put down synthetic high nitrogen fert unless it is a special.request. DPW will be helpful in NOT contributing to further thatch. The back lawn will be a test bed for different application rates of molasses.

My question or angle.is ......Do we need warmer temps to get the most bang for.the Buck for molasses application?


Well I did some 2.0" low mows on my lawn and in other spots 1.5". Other areas spring tine power raked a few other test areas. Other areas of the lawn will not be touched until it needs to be.mowed. I've documented this with pictures and I'm going to mark with white paint the borders of each area with just enough to be able to keep it visible.
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Excellent idea...

Molasses is only a food supply for the microbials... tempurature, definately is an important factor when it comes to microbial activity...
Much like moisture levels, temperature really dictates what the wee beasties are able to do...

I too grew the lawns long last season and will mow them short, just as soon as they start to grow...

Sometimes , picutures, can be decieving when you are looking for the health and well being of the turf for the entire season...
There is no question that turf 'greens up' quickly with an N boost as soon as it comes out of dormancy... we all understand 'Why" it happens and the client loves it... but,,, when summer comes, the 'thatch' that we've created is really starting to show its downside, as we try to get a healthy look to the lawns...

My research this year involves, a reasonable comparison to season long terrific lawn plus the great qucik "Geenup" of Spring...

What is, "DPW"?

Exact Rototilling
03-11-2012, 10:28 PM
DPW = Dried poultry waste = dried chicken poop

Which IMO begs the question what is more effective in thatch breakdown ....?

DPW vs the dirt from aeration cores [top dress effect] or molasses ....?

Might as well throw in most cost effective for.the client as well :rolleyes:
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Smallaxe
03-11-2012, 10:53 PM
DPW = Dried poultry waste = dried chicken poop

Which IMO begs the question what is more effective in thatch breakdown ....?

DPW vs the dirt from aeration cores [top dress effect] or molasses ....?

Might as well throw in most cost effective for.the client as well :rolleyes:
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Different foods, feed different microbes... that would mean,, that dpw would be helpful in 1 environment and molasses would be more effective in a deifferent environment... I don't know what the problem would be, in using either/or, even both...

To me , one needs a special reason to aerate in the Spring... Major 'overhaul' comes to mind... :)

Exact Rototilling
03-11-2012, 11:09 PM
Good point so then all 3 would work for my lawn. Each will have a key benefit.

As for aeration only for autumn or fall......? Demand is really low here and it is difficult to promote. From an income.generator......:( In this area there are a few who opt for it then but not many. I still don't completely understand it ....people in general "HERE" loose interest in lawns once the fall season rolls in.

I did at least 5-6 plugr 850 aerations last growing season even during warmer temp but grass height was.pushed up to 4" and I watch for signs of heat stress. I never did more than a double pass at once except in a few test areas because excessive plugs is bothersome when playing soccer or badminton etc.

Neighbor said the lawn has never looked better since we moved in. Also fairy ring has greatly faded....?

Again in ideal.conditions a healthy lawn with a vibrant night crawler population will not need core.aeration, true dethatching etcetera.
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Smallaxe
03-11-2012, 11:25 PM
That would be my thought... either molasses or dpw, should be great...

but:
Why do you do Spring aerations??

Exact Rototilling
03-12-2012, 01:18 AM
That would be my thought... either molasses or dpw, should be great...

but:
Why do you do Spring aerations??

In the case of my lawn... to help perforate the existing thatch layer buy punching and cutting through it. Lots of plugs on top of lawn for top.dress effect. Soil at the house here lacks night crawlers as well. In many areas here ground is hard and gravely and lacks good soil. Also most application Co here push aeration in.the Spring heavily and bundle it so.rates are beat down. Also aeration rentals are highest.this.time.of.year up till late May.or.so. If I.had.to.rely on fall aeration income I'd quit aerations completely.
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Exact Rototilling
03-12-2012, 01:23 AM
I too grew the lawns long last season and will mow them short, just as soon as they start to grow...



Can you.state.your reasons for only low.mowing in.the spring? Do you bag clippings then? I just side.discharged with G6 gators and.let.it sit this year.

Many LCOs and.homeowners want the super.short sub 2.25" mowing in the fall. I really resist anything lower.than 2.5" anytime unless I.get.more.$ for it.
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Smallaxe
03-12-2012, 05:29 AM
The reason that lawns are kept longer for the winter, is survival in case of drought... this winter was a good example in which the long thick grass protected the ground from drying out in the absence of snow cover...

In the Spring, when it starts to greenup, I mulch mow all the dead material down low and throw the molasses over it... hopefully, we get the Spring rains and the dead material covering the soil soon become a healthy part of the soil and the roots are going after water deeper into the ground... this helps prevent thatch...

Spring cut is around 2.25", Summer heat is cut around 3.5", Fall is back to 2.25" until the final cut of the year is back to 3.5"....

Smallaxe
03-12-2012, 05:45 AM
In the case of my lawn... to help perforate the existing thatch layer buy punching and cutting through it. Lots of plugs on top of lawn for top.dress effect. Soil at the house here lacks night crawlers as well. In many areas here ground is hard and gravely and lacks good soil. Also most application Co here push aeration in.the Spring heavily and bundle it so.rates are beat down. Also aeration rentals are highest.this.time.of.year up till late May.or.so. If I.had.to.rely on fall aeration income I'd quit aerations completely.
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Around here in the Spring with the frozen ground thawing and heaving, our soils are at there softest points of the year... Roots actively grow in the Spring as the ground thaws out, grass roots are filling up as much underground space as they can...
I think the earliest I would aerate would be around fertilizer time, after the 3rd mowing...

Anyways,,,
if you could find a source of compost, it might help your hard gravel soil by applying it after your aerations... having compost wash into those holes really helps...
Having long turf to mulch mow in the Spring may also help to establish a nite crawler population as well... :)

TruSomethingOrOther
03-13-2012, 04:25 AM
I will offer full throttle flail blade down and deep dirty for true thatch removal but it will be brutally expensive as it generates tremendous haul off.

Going to offer double, triple and quad passes with my Plugr ® 850's for a truly revolving amount of cores that the rolling tine guys can't touch. Followed by a G6 gator blade core break up.
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Where's the "like" button again????